A common power supply outputs a constant voltage. Disturbance, for example, input disturbance and output disturbance, needs to be suppressed to stabilize an output voltage of the power supply. Generally, a feedforward technology is used to suppress the input disturbance.
At present, most digital power feedforward technologies cannot meet requirements under various change slopes of an input voltage. Generally, when the input voltage changes slowly, timely sampling of the input voltage that rapidly changes cannot be implemented, resulting in a large fluctuation of the output voltage when the input voltage rapidly changes. Generally, when the input voltage changes rapidly, precision of sampling of the input voltage that slowly changes is insufficient, resulting in a small fluctuation of the output voltage when the input voltage slowly changes and causes a poor feedforward effect.